JapónJapan.Incidente de Kōfu · encuentro con ocupante y trazas físicas (Japón, 1975)Kōfu Incident · occupant encounter and physical traces (Japan, 1975)

At dusk on February 23, 1975, in the Kamimachi neighborhood of Kōfu (Yamanashi prefecture), near the Hinode housing estate, two primary-school boys, Masato Kawano and Katsuhiro Yamahata, both about seven years old, were roller-skating when they said they saw a pair of glittering orange objects in the sky. According to their account, one of the objects moved off toward Mount Atago while the other descended and landed among the rows of a vineyard behind the estate. They described a disc-shaped craft from which a short occupant emerged —a little over a meter tall, with a dark, wrinkled face and features the press later amplified as 'fangs.' The being supposedly approached and touched one of the boys on the shoulder, leaving him momentarily paralyzed with fear; it then allegedly walked around the craft and reboarded before the object took off.

What distinguishes the case from an isolated child sighting is the corroboration around the event. Several people said they saw the object or the lights: the boys' mothers, who on rushing out in alarm observed a large orange-red light hovering over the vineyard, Katsuhiro's younger brother, a classmate, a janitor and a woman driving through the area. The next morning, at the alleged landing site, neighbors found two solid concrete posts toppled or nearly fallen; when school staff investigated whether the children themselves could have knocked them over, they concluded it was impossible given their weight. One of the teachers took soil samples from the area —described as a circular patch— and measured them with a Geiger counter, reporting radioactivity levels he described as anomalous relative to the natural background.

Authorities offered a prosaic explanation: the Civil Aviation Bureau of the Transport Ministry maintained that what the boys saw was not a craft but the lights of a YS-11 propeller aircraft, the Japanese-built twin-engine plane in common use at the time. The explanation has an obvious limit: it can account for the orange lights in the sky —and even the light the mothers saw— but not the landing, the occupant, the physical effect on the boy or the toppled posts. At the same time, none of those remaining elements has backing that raises it above testimony: the posts could have fallen from mundane causes before or after, the Geiger reading was taken by a teacher with no forensic protocol or chain of custody, and the central component —the occupant— rests on two seven-year-old witnesses. The case remained one of Japan's best-known close encounters, with no agreed resolution: neither the boys' version has instrumental evidence confirming it, nor does the official explanation cover the whole account.

Es el primer encuentro cercano con ocupante (CE3) asiático del corpus y un clásico de la ufología japonesa — aporta una categoría morfológica que faltaba en la cobertura de Asia, dominada por luces y casos institucionales. Su interés está en la mezcla poco habitual de testimonio infantil con elementos verificables a posteriori: testigos adultos independientes, dos postes de concreto derribados que la escuela determinó que los niños no pudieron tumbar, y una medición de radiactividad anómala en el suelo. Nada de eso es prueba —las trazas no fueron analizadas por un laboratorio independiente y el contador Geiger lo manejó un profesor, no un equipo forense— pero eleva el caso por encima del rumor. Se mantiene en Tier B con probabilidad baja por su debilidad estructural: testigos centrales que eran niños, ausencia de instrumentación, riesgo de amplificación mediática (los 'colmillos') y una explicación oficial viva (el YS-11) que, aunque parcial, cubre la parte aérea. Es el contrapeso honesto: un caso famoso, sugerente y a la vez frágil.

It is the corpus's first Asian close encounter with an occupant (CE3) and a classic of Japanese ufology — it adds a morphological category missing from Asia's coverage, which is dominated by lights and institutional cases. Its interest lies in the unusual mix of child testimony with elements verifiable after the fact: independent adult witnesses, two concrete posts toppled that the school determined the children could not have knocked over, and a measurement of anomalous soil radioactivity. None of that is proof —the traces were not analyzed by an independent lab and the Geiger counter was handled by a teacher, not a forensic team— but it raises the case above rumor. It stays at Tier B with low probability because of its structural weakness: central witnesses who were children, absence of instrumentation, risk of media amplification (the 'fangs'), and a live official explanation (the YS-11) that, though partial, covers the aerial part. It is the honest counterweight: a famous, suggestive and at the same time fragile case.